Scientists often take an epidemiological approach to a phenomenon to discover clues about its cause and nature. This is not limited to medical diseases, the basic concept can apply to any episodic event.
Take UFO sightings – the phenomenon in question is people reporting that they saw something unidentified in the sky. We can generate some basic hypotheses about factors that might influence UFO sightings: the presence of objects to be observed, viewing conditions, number of people available to make observations, and priming (the idea of UFOs in the culture, say following a movie about UFOs or a case reported in the media).
As reported by The Economist, the National UFO Reporting Center has released statistics on UFO sightings by state and by time of day. The Economist has conveniently placed this data in an infographic, depicted right. They helpfully labeled the three periods of the day as working hours, drinking hours, and sleeping hours. As you can see, UFO reports peak during the drinking hours.
I am going to assume the article is tongue-in-cheek, but it is being spread around social media, sometimes in a manner that seems credulous.
I don’t doubt the data itself, but the labeling of the chart amounts to begging the question – calling the evening hours the “drinking hours” makes certain assumptions about cause and effect. A far simpler explanation for the peak of sightings in the evening is that night-time conditions are more conducive to seeing unidentified lights in the sky, and people are still awake.
The article cheekily states that aliens don’t disturb us while we sleep (don’t tell that to people who experience hypnagogia and interpret the experience as an alien abduction), but obviously people are simply not in a position to make observations while they sleep.
Therefore we don’t need to invoke alcohol consumption at all to explain the pattern seen in this data.
There are, however, patterns in the UFO data that . . .
UFO over Hollywood (FL) and Dania Beach or was it a Delta rocket that formed a strange cloud in the sky
By Ihosvani Rodriguez, Sun Sentinel via OrlandoSentinel.com
Some thought it was a spotlight. Others wondered whether aliens were visiting us from afar.
One person joked it was probably “swamp gas” from Florida.
Turns out it wasn’t one of theirs from a distant galaxy, it was one of ours.
Hundreds — perhaps thousands — across Florida witnessed a white or bluish cloud shining in Wednesday’s sky just before dusk shortly after a Delta IV rocket was launched from Brevard County. Reports of the peculiar spectacle came from as far north as Jacksonville and down to the Florida Keys, U.S. Air Force officials said.
Meteorologists in Melbourne said the sight was nothing to be alarmed about. “There is no reason to be freaking out,” laughed National Weather Service meteorologist John Pendergrast, based in Brevard County.
Scientists believe the swirly white or electric-bluish cloud was caused by the exhaust plume of the rocket, which formed a cloud of ice crystals 240,000 to 280,000 feet above Earth. The illumination was caused by the sun still shining at that height.
The two spacecraft with red lights that some reported seeing were likely the rocket booster and the rocket separating from each other, officials said. The formation of the cloud and the 8:29 p.m. launch time made conditions ripe for the spectacular sight.
“You can only get that effect at certain times of the day,” Pendergrast said. “It was perfect timing. We knew before the launch we would be seeing something interesting in the sky.”
The same phenomenon was widely reported in South Florida in 2009, shortly after the launch of space shuttle Discovery.